/*
 * Copyright (C) 2021 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package me.panpf.sketch.sample.util;

import ohos.agp.utils.Point;
import ohos.agp.window.service.Display;
import ohos.agp.window.service.DisplayManager;
import ohos.app.Context;

import java.text.DecimalFormat;
import java.util.concurrent.atomic.AtomicInteger;

/**
 * PxUtil
 */
public class PxUtil {
    private static Display display;

    /**
     * initContext
     * @param context
     */
    public static void initContext(Context context) {
        display = DisplayManager.getInstance().getDefaultDisplay(context).get();
    }

    /**
     * screenWidth
     * @return int
     */
    public static int screenWidth() {
        return display.getAttributes().width;
    }

    /**
     * screenHeight
     * @return int
     */
    public static int screenHeight() {
        return display.getAttributes().height;
    }

    /**
     * getScreenSize
     * @return Point
     */
    public static Point getScreenSize() {
        Point pt = new Point();
        display.getSize(pt);
        return pt;
    }

    /**
     * fp2px
     * @param fp fp
     * @return float
     */
    public static float fp2px(float fp) {
        float sca = display.getAttributes().scalDensity;
        return (float) (fp * sca + 0.5d * (fp >= 0 ? 1 : -1));
    }

    /**
     * vp2px
     * @param vp vp
     * @return float
     */
    public static float vp2px(float vp) {
        float dpi = display.getAttributes().densityPixels;
        return (float) (vp * dpi + 0.5d * (vp >= 0 ? 1 : -1));
    }


    /**
     * 格式化数字(保留一位小数)
     *
     * @param num 数字
     * @return 格式化数字(保留一位小数)
     */
    public static String formatNum(int num) {
        DecimalFormat format = new DecimalFormat("0");
        return format.format(num);
    }

    /**
     * 格式化数字(保留两位小数)
     *
     * @param num 数字
     * @return 格式化数字(保留两位小数)
     */
    public static String formatNum(float num) {
        if (((int) num * 1000) == (int) (num * 1000)) {
            // 如果是一个整数
            return String.valueOf((int) num);
        }
        DecimalFormat format = new DecimalFormat("0.00");
        return format.format(num);
    }


    private static final AtomicInteger NEXT_GENERATED_ID = new AtomicInteger(1);

    /**
     * 主动生成viewid,防止冲突
     *
     * @return id
     */
    public static int generateViewId() {
        for (; ; ) {
            final int result = NEXT_GENERATED_ID.get();
            int newValue = result + 1;
            if (newValue > 0x00FFFFFF) {
                // Roll over to 1, not 0.
                newValue = 1;
            }
            if (NEXT_GENERATED_ID.compareAndSet(result, newValue)) {
                return result;
            }
        }
    }

}
